Exploring the Shear Performance and Predictive Shear Capacity of Corroded RC Columns Utilizing the Modified Compression-Field Theory: an Investigative Study

Corrosion damage substantially weakens the shear strength of reinforced concrete (RC) structures, severely compromising their seismic resistance. Therefore, developing an accurate constitutive model is imperative to investigate the impact of corrosion damage on the shear resistance of RC structures. This study presents a corroded RC shear constitutive model based on the modified compression-field theory (MCFT). To capture the flexural, shear, and slip responses of corroded RC columns accurately, a nonlinear analysis model based on OpenSees is proposed. Comparing the results from four sets of quasi-static tests reveals that the proposed constitutive model and analysis framework can well simulate the seismic performance of corroded RC columns. Based on the comparative analysis, the influence of corrosion-induced damage, reinforcement ratio, and axial load on the shear performance of RC columns is discussed. The investigation findings reveal that high corrosion levels and low reinforcement ratios remarkably weaken the shear strength of RC columns. Additionally, high axial load levels accelerate the rate of post peak shear stress degradation. Moreover, this study proposes a method for estimating the shear strength of corroded RC columns based on the MCFT. The presented approach provides a solid foundation for evaluating the shear and seismic performance of existing RC structures.